May 19, 2026

Sienna Miller Wore Colleen Allen On The Tonight Show Starring Jimmy Fallon

Sienna Miller made a guest appearance on The Tonight Show Starring Jimmy Fallon last week, where the British actress talked about having a newborn, a toddler, and a teenager, meeting Nicolas Cage during a screen test for National Treasure, and John Krasinski writing the role of Agent Marlow for her in the film Jack Ryan: Ghost War.

Sienna Miller wearing a marigold Colleen Allen dress on The Tonight Show Starring Jimmy Fallon.
Todd Owyoung/NBC

It must be said that Colleen Allen has one of the best PR agents in fashion, because the label consistently lands major celebrity placements. And any brand that managed to convince a stylist to put their client in this marigold jacquard dress not once, but twice, deserves some kind of industry award.

Sienna Miller wore Colleen Allen marigold jacquard slip dress with white pumps for her Jimmy Fallon appearance.
Todd Owyoung/NBC

When Rose Byrne wore this look last month, I wished she had removed the coat, and here I am getting my wish.

In fairness, I do believe this dress could work on the right person, but it feels so misaligned with everything we know about Sienna Miller’s style. The rich marigold tone and slinky jacquard texture almost call for someone with a deeper complexion or taller as the dress is so long.

Sienna Miller styled a marigold Colleen Allen jacquard slip dress with white pumps for her Jimmy Fallon appearance.
Todd Owyoung/NBC

On Sienna, it just feels slightly disconnected, but the styling with white shoes works, it has to be said.

Stylist: Gabriella Karefa-Johnson.

Colleen Allen Spring 2026

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